* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* Original copyright notice is retained at the end of this file.
*/
* The previous version did not allow 4-digit octals.
*/
-#include "busybox.h"
+#include "libbb.h"
-int bb_echo(char **argv)
+/* This is a NOFORK applet. Be very careful! */
+
+/* NB: can be used by shell even if not enabled as applet */
+
+int echo_main(int argc UNUSED_PARAM, char **argv)
{
const char *arg;
#if !ENABLE_FEATURE_FANCY_ECHO
eflag = '\\',
nflag = 1, /* 1 -- print '\n' */
};
- ++argv;
+
+ /* We must check that stdout is not closed.
+ * The reason for this is highly non-obvious.
+ * echo_main is used from shell. Shell must correctly handle "echo foo"
+ * if stdout is closed. With stdio, output gets shoveled into
+ * stdout buffer, and even fflush cannot clear it out. It seems that
+ * even if libc receives EBADF on write attempts, it feels determined
+ * to output data no matter what. So it will try later,
+ * and possibly will clobber future output. Not good. */
+// TODO: check fcntl() & O_ACCMODE == O_WRONLY or O_RDWR?
+ if (fcntl(1, F_GETFL) == -1)
+ return 1; /* match coreutils 6.10 (sans error msg to stderr) */
+ //if (dup2(1, 1) != 1) - old way
+ // return 1;
+
+ arg = *++argv;
+ if (!arg)
+ goto newline_ret;
#else
const char *p;
char nflag = 1;
char eflag = 0;
+ /* We must check that stdout is not closed. */
+ if (fcntl(1, F_GETFL) == -1)
+ return 1;
+
while (1) {
arg = *++argv;
if (!arg)
}
#if !ENABLE_FEATURE_FANCY_ECHO
/* SUSv3 specifies that octal escapes must begin with '0'. */
- if ( (((unsigned char)*arg) - '1') >= 7)
+ if ( ((int)(unsigned char)(*arg) - '0') >= 8) /* '8' or bigger */
#endif
{
/* Since SUSv3 mandates a first digit of 0, 4-digit octals
* of the form \0### are accepted. */
- if (*arg == '0' && ((unsigned char)(arg[1]) - '0') < 8) {
- arg++;
+ if (*arg == '0') {
+ /* NB: don't turn "...\0" into "...\" */
+ if (arg[1] && ((unsigned char)(arg[1]) - '0') < 8) {
+ arg++;
+ }
}
- /* bb_process_escape_sequence can handle nul correctly */
+ /* bb_process_escape_sequence handles NUL correctly
+ * ("...\" case). */
c = bb_process_escape_sequence(&arg);
}
}
- putchar(c);
+ bb_putchar(c);
}
arg = *++argv;
if (!arg)
break;
- putchar(' ');
+ bb_putchar(' ');
}
-#if ENABLE_FEATURE_FANCY_ECHO
newline_ret:
-#endif
if (nflag) {
- putchar('\n');
+ bb_putchar('\n');
}
ret:
- return fflush(stdout);
-}
-
-/* This is a NOFORK applet. Be very careful! */
-
-int echo_main(int argc, char** argv);
-int echo_main(int argc, char** argv)
-{
- return bb_echo(argv);
+ return fflush_all();
}
/*-
*
* @(#)echo.c 8.1 (Berkeley) 5/31/93
*/
+
+#ifdef VERSION_WITH_WRITEV
+/* We can't use stdio.
+ * The reason for this is highly non-obvious.
+ * echo_main is used from shell. Shell must correctly handle "echo foo"
+ * if stdout is closed. With stdio, output gets shoveled into
+ * stdout buffer, and even fflush cannot clear it out. It seems that
+ * even if libc receives EBADF on write attempts, it feels determined
+ * to output data no matter what. So it will try later,
+ * and possibly will clobber future output. Not good.
+ *
+ * Using writev instead, with 'direct' conversion of argv vector.
+ */
+
+int echo_main(int argc, char **argv)
+{
+ struct iovec io[argc];
+ struct iovec *cur_io = io;
+ char *arg;
+ char *p;
+#if !ENABLE_FEATURE_FANCY_ECHO
+ enum {
+ eflag = '\\',
+ nflag = 1, /* 1 -- print '\n' */
+ };
+ arg = *++argv;
+ if (!arg)
+ goto newline_ret;
+#else
+ char nflag = 1;
+ char eflag = 0;
+
+ while (1) {
+ arg = *++argv;
+ if (!arg)
+ goto newline_ret;
+ if (*arg != '-')
+ break;
+
+ /* If it appears that we are handling options, then make sure
+ * that all of the options specified are actually valid.
+ * Otherwise, the string should just be echoed.
+ */
+ p = arg + 1;
+ if (!*p) /* A single '-', so echo it. */
+ goto just_echo;
+
+ do {
+ if (!strrchr("neE", *p))
+ goto just_echo;
+ } while (*++p);
+
+ /* All of the options in this arg are valid, so handle them. */
+ p = arg + 1;
+ do {
+ if (*p == 'n')
+ nflag = 0;
+ if (*p == 'e')
+ eflag = '\\';
+ } while (*++p);
+ }
+ just_echo:
+#endif
+
+ while (1) {
+ /* arg is already == *argv and isn't NULL */
+ int c;
+
+ cur_io->iov_base = p = arg;
+
+ if (!eflag) {
+ /* optimization for very common case */
+ p += strlen(arg);
+ } else while ((c = *arg++)) {
+ if (c == eflag) { /* Check for escape seq. */
+ if (*arg == 'c') {
+ /* '\c' means cancel newline and
+ * ignore all subsequent chars. */
+ cur_io->iov_len = p - (char*)cur_io->iov_base;
+ cur_io++;
+ goto ret;
+ }
+#if !ENABLE_FEATURE_FANCY_ECHO
+ /* SUSv3 specifies that octal escapes must begin with '0'. */
+ if ( (((unsigned char)*arg) - '1') >= 7)
+#endif
+ {
+ /* Since SUSv3 mandates a first digit of 0, 4-digit octals
+ * of the form \0### are accepted. */
+ if (*arg == '0' && ((unsigned char)(arg[1]) - '0') < 8) {
+ arg++;
+ }
+ /* bb_process_escape_sequence can handle nul correctly */
+ c = bb_process_escape_sequence( (void*) &arg);
+ }
+ }
+ *p++ = c;
+ }
+
+ arg = *++argv;
+ if (arg)
+ *p++ = ' ';
+ cur_io->iov_len = p - (char*)cur_io->iov_base;
+ cur_io++;
+ if (!arg)
+ break;
+ }
+
+ newline_ret:
+ if (nflag) {
+ cur_io->iov_base = (char*)"\n";
+ cur_io->iov_len = 1;
+ cur_io++;
+ }
+ ret:
+ /* TODO: implement and use full_writev? */
+ return writev(1, io, (cur_io - io)) >= 0;
+}
+#endif
projects / oweals / busybox.git / blobdiff